28404865 has 8 divisors (see below), whose sum is σ = 34213248. Its totient is φ = 22638960.

The previous prime is 28404853. The next prime is 28404881. The reversal of 28404865 is 56840482.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28404865 - 2⁹ = 28404353 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9127 + ... + 11836.

It is an arithmetic number, because the mean of its divisors is an integer number (4276656).

Almost surely, 2^28404865 is an apocalyptic number.

It is an amenable number.

28404865 is a deficient number, since it is larger than the sum of its proper divisors (5808383).

28404865 is a wasteful number, since it uses less digits than its factorization.

28404865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21239.

The product of its (nonzero) digits is 61440, while the sum is 37.

The square root of 28404865 is about 5329.6214687349. The cubic root of 28404865 is about 305.1154807711.

The spelling of 28404865 in words is "twenty-eight million, four hundred four thousand, eight hundred sixty-five".